Finding the Fourth Proportional to 1,388.88, 2,086.56 and 1,281.96

Step by Step Solution

1. Step 1: Write the proportion equation
   1,388.88 : 2,086.56 = 1,281.96 : x
2. Step 2: Convert to fraction form
   1,388.88/2,086.56 = 1,281.96/x
3. Step 3: Cross multiply
   1,388.88x = 2,086.56 × 1,281.96
4. Step 4: Simplify right side
   1,388.88x = 2,674,886.46
5. Step 5: Solve for x
   x = 2,674,886.46/1,388.88
6. Step 6: Final answer
   x = 1,925.93